1. Field of the Invention
The present invention relates to reversible ratchet wrenches and, in particular to the disposition and retention of a reversing lever, a pawl, a gear, and a cover plate using a single screw.
2. Description of the Prior Art
The reversible ratchet wrench has been known for many years and there are numerous ratchet tools with varying handles, driver assemblies, pawl assemblies, and reversing levers.
Recently, there has been a demand for a ratchet wrench which has comparatively few separate parts, thus significantly reducing the need for expensive and extensive tooling and parts inventory, which ratchet wrench can also be assembled easily and rapidly by relatively unskilled labor, and for which wrench, repairs and replacement of parts can be easily accomplished.
One such wrench is disclosed in U.S. Pat. No. 5,178,047 to Arnold et al. This wrench reduces the number of separate parts common in prior tools, by eliminating the need for washers and retaining rings, as well as the number of screws needed to join conventional parts, such as the gear assembly, the pawl assembly, and the reversing lever. This is made possible by the cooperative engagement of the pawl and gear assemblies with a uniquely configured reversing lever having a complex geometry. Due to the nature and construction of the cooperating parts, additional parts are obviated. In particular, the Arnold wrench comprises a reversing lever having a top portion, a tab extending outwardly therefrom and a stem depending downwardly from the top portion. The stem is received in a vertical bore in the pawl to permit rotation of the pawl between a first or forward condition and a second or reverse condition. The teeth on the pawl selectively engage the teeth on a gear to permit rotation of the gear, as well as of a socket or other driver connected thereto. The wrench further includes a body having first and second part-circular cavities formed therein and communicating with each other. Through the first and second cavities are received the gear and lever/pawl assemblies, respectively. The unique geometry of the reverse lever relative to the pawl and the gear in combination with a cover plate cooperate to hold the assemblies in their respective cavities, once assembly is completed. The use of the cover plate is important to reduce the entry of dirt into the cavities, as well as to reduce wear and damage to the gear and pawl assemblies, to retain the gear and pawl and to provide a bearing surface therefore.
While the Arnold wrench is an improvement over tools requiring a greater number of cooperating parts, the complex geometry of the reversing lever, the gear and pawl assemblies, and the coverplate makes tooling of individual parts an arduous and expensive process.